(29P) Schwassmann-Wachmann


This object has a more recent orbit available here

Object

Object (29P) Schwassmann-Wachmann
Diameter(1) 60 km
Dynamic class(1) comet
Absolute magnitude 5.85
G slop 0.20
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2457754.5
Semi major axis 6.016546 ± 0.000001 au
Eccentricity 0.041745069 ± 0.000000158
Inclination 9.375666799 ± 0.000012310 °
Longitude of ascending node 312.410154 ± 0.000072 °
Argument of perihelia 48.702170 ± 0.000403 °
Mean anomaly 305.976080 ± 0.000388 °
Orbital period 14.76 yr

Ephemeris & Observations

Ephemeris version NIMAv2
Observation file (documentation) omc_ast_NIMAv2.txt
bsp file 29P_Schwassmann-Wachmann_nima_v2.bsp
Date of first observation 2009-02-17
Date of last observation 2020-11-19
Number of observations used in the fit 559
Number of rejected observations 0
Number of DES observations 0
Number of MPC observations 0
Number of unpublished observations 559
RMS of observations 0.079 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv2 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2022-01 0.149 0.053
2022-07 0.145 0.041
2023-01 0.232 0.068
2023-07 0.189 0.068
2024-01 0.290 0.133
2024-07 0.229 0.111
2025-01 0.325 0.187
2025-07 0.268 0.153
2026-01 0.350 0.206

Ephemeris comparison

residual plot

Difference between NIMAv2 and JPLK192-43 in right ascension (weighted by cos δ) and in declination.
Gray area represents the 1-σ uncertainty of NIMA ephemeris. Green dots represent the DES observations.